%0 Journal Article %T Physical Conditions in Lyman Break Galaxies Derived From Rest-Frame UV Spectra %A A. E. Shapley %A C. C. Steidel %A K. L. Adelberger %A Max Pettini %J Physics %D 2001 %I arXiv %X We present the results of detailed studies of the astrophysical conditions in z~3 Lyman Break Galaxies (LBGs), placing particular emphasis on what is learned from LBG rest frame UV spectra. By drawing from our database of ~1000 spectra, and constructing higher S/N composite spectra from galaxies grouped according to properties such as luminosity, extinction, morphology, and environment, we can show how the rest-frame UV spectroscopic properties systematically depend on other galaxy properties. Such information is crucial to understanding the detailed nature of LBGs, and their impact on the surrounding IGM. %U http://arxiv.org/abs/astro-ph/0112262v1